<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        let money=10000;
        while (true) {
            let cz = prompt(`
            请输入您的操作：
            1、存钱
            2、取钱
            3、查看余额
            4、退出
            `);
            switch (cz) {
                case '1':
                    let c=prompt('请输入您要存的余额');
                    money+=c;
                    alert(money);
                    break;

                case '2':
                    let q=prompt('请输入您要取出的余额');
                    money-=q;
                    alert(money);
                    break;

                case '3':
                alert(`您的余额还有${money}`);
                    break;
                
                default:
                    break;
            }
            if (cz==='4') {
                alert('退出成功');
                break;
            }
        }
    </script>
</body>
</html>